Abstract
BACKGROUND: Red meat consumption has been associated with an increased risk of chronic diseases. However, its relationship with mortality remains uncertain. METHODS: We prospectively observed 37 698 men from the Health Professionals Follow-up Study (1986-2008) and 83 644 women from the Nurses’ Health Study (1980-2008) who were free of cardiovascular disease (CVD) and cancer at baseline. Diet was assessed by validated food frequency questionnaires and updated every 4 years. RESULTS: We documented 23 926 deaths (including 5910 CVD and 9464 cancer deaths) during 2.96 million person-years of follow-up. After multivariate adjustment for major lifestyle and dietary risk factors, the pooled hazard ratio (HR) (95% CI) of total mortality for a 1-serving-per-day increase was 1.13 (1.07-1.20) for unprocessed red meat and 1.20 (1.15-1.24) for processed red meat. The corresponding HRs (95% CIls) were 1.18 (1.13-1.23) and 1.21 (1.13-1.31) for CVD mortality and 1.10 (1.06-1.14) and 1.16 (1.09-1.23) for cancer mortality. We estimated that substitutions of 1 serving per day of other foods (including fish, poultry, nuts, legumes, low-fat dairy, and whole grains) for 1 serving per day of red meat were associated with a 7% to 19% lower mortality risk. We also estimated that 9.3% of deaths in men and 7.6% in women in these cohorts could be prevented at the end of follow-up if all the individuals consumed fewer than 0.5 servings per day (approximately 42 g/d) of red meat. CONCLUSIONS: Red meat consumption is associated with an increased risk of total, CVD, and cancer mortality. Substitution of other healthy protein sources for red meat is associated with a lower mortality risk.
Generated Summary
This study, published in the Archives of Internal Medicine, investigated the relationship between red meat consumption and mortality in two prospective cohort studies: the Health Professionals Follow-up Study (men, 1986-2008) and the Nurses’ Health Study (women, 1980-2008). The research aimed to determine if there was an association between red meat consumption and the risk of total mortality, cardiovascular disease (CVD) mortality, and cancer mortality. The study utilized data from a large number of participants who were initially free of CVD and cancer, with dietary information collected through validated food frequency questionnaires. The study employed a prospective observational design, following participants over several years to document deaths and assess dietary habits. Statistical analyses, including multivariate adjustments for various lifestyle and dietary risk factors, were conducted to evaluate the associations between red meat intake and mortality outcomes. The study’s methodology involved the collection and analysis of extensive data from two large cohorts, allowing for a robust assessment of the relationship between red meat consumption and mortality.
Key Findings & Statistics
- The study documented 23,926 deaths during 2.96 million person-years of follow-up.
- For unprocessed red meat, the pooled hazard ratio (HR) for total mortality was 1.13 (95% CI: 1.07-1.20) for a 1-serving-per-day increase.
- For processed red meat, the pooled HR for total mortality was 1.20 (95% CI: 1.15-1.24) for a 1-serving-per-day increase.
- The corresponding HRs (95% CI) for CVD mortality were 1.18 (1.13-1.23) and 1.21 (1.13-1.31).
- The HRs (95% CI) for cancer mortality were 1.10 (1.06-1.14) and 1.16 (1.09-1.23).
- Substituting 1 serving per day of other foods (fish, poultry, nuts, legumes, low-fat dairy, and whole grains) for 1 serving per day of red meat was associated with a 7% to 19% lower mortality risk.
- The study estimated that 9.3% of deaths in men and 7.6% in women could be prevented if individuals consumed fewer than 0.5 servings per day (approximately 42 g/d) of red meat.
Other Important Findings
- Red meat consumption was associated with an increased risk of total mortality.
- Red meat consumption was associated with an increased risk of CVD mortality.
- Red meat consumption was associated with an increased risk of cancer mortality.
- Substituting red meat with other healthy protein sources was associated with a lower mortality risk.
Limitations Noted in the Document
- The study’s reliance on food frequency questionnaires, while validated, may be subject to recall bias and inaccuracies in self-reported dietary intake.
- Observational studies cannot establish causality; therefore, the study can only demonstrate associations, not prove that red meat consumption directly causes increased mortality.
- The study did not account for the specific methods of red meat preparation or the types of red meat consumed, which could influence health outcomes.
- The study focused on two specific cohorts (Health Professionals and Nurses), and the findings may not be generalizable to other populations with different dietary habits, lifestyle factors, and genetic predispositions.
- The study did not fully explore the impact of specific nutrients or compounds in red meat on mortality risk, which might provide more detailed insights into the underlying mechanisms.
Conclusion
The study’s findings highlight the significant association between red meat consumption and increased mortality risk, including total mortality, CVD mortality, and cancer mortality. The data strongly suggests that higher red meat intake is linked to adverse health outcomes, underscoring the need for dietary modifications to mitigate these risks. The study’s emphasis on the benefits of substituting red meat with other protein sources provides a straightforward dietary strategy for lowering mortality risk. A key takeaway is the recommendation to replace red meat with healthier alternatives, such as fish, poultry, nuts, legumes, low-fat dairy, and whole grains. This dietary shift has the potential to improve overall health and longevity, as indicated by the study’s findings on reduced mortality. The research underscores the complex relationship between diet and health, providing strong evidence that dietary choices can have a significant effect on public health. The implication is that public health initiatives should focus on educating the public about the risks associated with high red meat consumption and the benefits of incorporating healthier protein sources into their diets. Further studies are needed to investigate the specific mechanisms through which red meat affects mortality and to explore the potential of various dietary interventions to enhance public health outcomes. This study contributes valuable insights into the ongoing discussions about dietary guidelines and recommendations, promoting the adoption of healthier dietary patterns for improved health outcomes.